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IV.D.1. (XII.C.1.)

Geometry Comparison

C4H4N2 (1,3-Diazine)


distance is atom 2 (C) to atom 6 (N)

Experimental bond length is 1.328  Å

original data displayed. press to display differences
differences displayed. press to display original data

Calculated bond length in Å
Methods with predefined basis sets
semi-empirical PM3 1.357
PM6 1.376
composite G2 1.319
G3 1.319
G3B3 1.338

Calculated bond length in Å
Methods with standard basis sets
STO-3G 3-21G 3-21G* 6-31G 6-31G* 6-31G** 6-31+G** 6-311G* 6-311G** 6-31G(2df,p) 6-311+G(3df,2p) TZVP cc-pVDZ cc-pVTZ aug-cc-pVDZ aug-cc-pVTZ
hartree fock HF 1.354 1.329 1.329 1.330 1.319 1.319 1.320 1.317 1.318 1.316 1.315 1.316 1.320 1.315 1.321 1.315
density functional LSDA 1.386 1.344 1.344 1.345 1.332 1.332 1.333 1.328 1.328 1.328     1.333 1.326 1.333  
SVWN   1.342     1.332   1.334                  
BLYP 1.413 1.365   1.365 1.351 1.351 1.352   1.348 1.348     1.353 1.345 1.352  
B1B95 1.383 1.345 1.345 1.345 1.330 1.332 1.332 1.329 1.329 1.329     1.333 1.325 1.331  
B3LYP 1.392 1.350 1.350 1.351 1.338 1.338 1.339 1.335   1.334 1.332 1.334 1.339 1.332    
B3LYPultrafine         1.338   1.339                  
B3PW91   1.348 1.348 1.348 1.335 1.335   1.332   1.332     1.336 1.330 1.336  
mPW1PW91   1.345   1.346 1.332 1.332 1.333 1.329 1.330 1.329     1.334   1.333  
M06-2X         1.333                      
PBEPBE   1.361     1.346 1.346 1.347 1.343 1.343 1.343 1.340   1.347 1.341    
PBEPBEultrafine         1.346                      
HSEh1PBE         1.333                      
Moller Plesset perturbation MP2FC   1.366 1.366 1.369 1.342 1.342 1.344 1.341 1.341 1.338   1.338 1.347 1.337    
MP2FU         1.341     1.340                
MP3         1.337                      
B2PLYP         1.339   1.340                  
Quadratic configuration interaction QCISD                 1.339              

Calculated bond length in Å
Methods with effective core potentials (select basis sets)
CEP-31G CEP-31G* CEP-121G CEP-121G* LANL2DZ SDD
hartree fock HF 1.344 1.330 1.342 1.326 1.336 1.336
density functional B1B95 1.361 1.345        
B3LYP 1.369 1.351 1.365 1.346 1.357 1.358
Moller Plesset perturbation MP2FC 1.391 1.357 1.383 1.352 1.379 1.379
Values that are outliers may reflect different atom numbering for different levels of theory.
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